


Monster in the Woods

by LemonKat (orphan_account)



Category: Undertale (Video Game)
Genre: Dom Sans, Ecto-Tongue, Ecto-dick, F/M, Licking, No Plot/Plotless, One Shot, Post-Pacifist Route, Reader Is Not Frisk, Rough Sex, Sex in the woods, Sexual Tension, Short Sans, Smut, reader is female, reader is kinky, slight fear fetish
Language: English
Status: Completed
Published: 2016-01-31
Updated: 2016-01-31
Packaged: 2018-05-17 08:53:14
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 5,754
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5862586
Author URL: https://archiveofourown.org/users/orphan_account/pseuds/LemonKat
Summary: <blockquote class="userstuff">
              <p>It was a cool winter evening. No snow yet on the ground, however the air was crisp with the cold. A lithe figure trailed along the outskirts of the woods next to the town. The trees enclosed around a mountain filled with rumor of monsters. There had always been the myths, but only recently did they start to become real.</p>
            </blockquote>





	Monster in the Woods

**Author's Note:**

> Here we go! This was a fic suggested by the lovely @peaches-and-screams on tumblr! It features Sans with a female!reader and to be inspired by the song Little Red Riding Hood by Amanda Seyfried. Enjoy!

It was a cool winter evening. No snow yet on the ground, however the air was crisp with the cold. A lithe figure trailed along the outskirts of the woods next to the town. The trees enclosed around a mountain filled with rumor of monsters. There had always been the myths, but only recently did they start to become real.

The woman standing in front of the trees did not seem to give it much warning as her path was to cut through it. She had a destination through the dense foliage, and scoffed at the notion of scary monsters in the woods.

Still, she hesitated at the tree line, her breath already heavy and her heart thudding in her ears. With a confident shake she pulled her long red coat closer to her body. It was form fitting as it wrapped around her in a complimenting manner. It was her favorite.

With an air of confidence she took a deep breath to calm herself of the intimidating trek ahead. There was an actual path thankfully. A small one, but it was better than trying to shove through the brush of the back wood. She just wanted to get through there before night fell.

Of course she could have just gone the long way around the woods. That would have taken longer and she did not have a car to make the trip easier. Downsides of living in a small town meant rarely owning a car since most things were a walk away. This trip unfortunately was not one of those as she kept her eyes forward on the dirt path.

Crunch. The noise of twigs snapping on the ground alerted her from her thoughts. Like a deer caught in the headlights she darted her head around, stopping her strides. This was not the time to be getting spooked. Calming down quickly she saw nothing in the dimly lit tree lines.

She rubbed at her arms as the chill in the air reminded her it was winter. This also meant it would be getting darker much earlier as she cursed to herself. She was already losing light as she tried to pick up her pace.

With fear beginning to creep into her mind after being spooked once she made mental note of just taking the long way next time. She would hassle a friend or co-worker for a ride if she had to.

Her thoughts were interrupted by yet another sound. She was going to put it off, however it was even louder, feeling as though it was right behind her. Turning sharply as if expecting some sort of attack her eyes were wide with fear. She saw... absolutely nothing. Her heart thudded in her head which made her notice her panted breaths.

Now she was just hearing things she thought, her hand moving up to rub the back of her neck. She could feel a very mild cold sweat there already as she was not handling this late evening woods walk that well. Glancing down she saw that the pathway behind her was much more disturbed than what she caused herself.

She really tried not to think about it as she turned around to continue her path. Her pace quickened as she thought over how it should not take her more than maybe a hour of an easy going walk to reach where she needed to be. Once she reached the other side of the woods she would be fine and could stop letting the talks of monsters begin to get to her.

As if to calm herself down she gave a chuckle under her breath thinking of how silly the rumors had been. A child leading monsters out of a mountain that was better known as a death trap. She froze again as her giggles to herself had stopped, but she could still hear a laughter.

It was deep and rumbling in her ears. Now she was terrified, clenching at the front of her coat. Another cackle echoed, but this time it was as if it was right against her ear. She could even feel the hot breath hit the side of her face.

She breathed in sharply, jumping backwards only to see nothing there again. A bead of sweat rolled down her neck as she darted her eyes around in panic. Her lower lip quivered before biting down on it to try to gain some confidence in the situation.

"W-who's there," she finally stuttered out in her panic. Maybe they were friendly? She could only hope as she pressed her thighs together ever so slightly. Not really the time to be feeling a mild heat. She put it off as just her fear getting to her as things went silent for a long moment.

"that any way to greet a new pal, lady," that deep voice that had been taunting her with low laughter now spoke clearly. It was directly behind her which the words caught her off guard in the middle of her panicked state. She turned quickly anyway, tensing up not sure what or who she would be facing.

What she saw she really was not expecting. She thought it would be a tall man, probably a creep sneaking up on her cause she was out late. Instead her eyes had to dart down at the figure before her. He must have been a couple inches shorter than her as the fear now turned into confusion.

It re-lit though as she squinted through the growing darkness of the late evening to see two white lights staring up at her. They were in eye sockets. A skull! She paled instantly as she realized it was a walking skeleton. Her every logical thought was telling her to scream and run, however before she made any rash choices her eyes trailed down.

His mouth was in a high set grin that was almost comical. The more she looked at him the less scared she got as she looked over his blue parka and its fur lined hood. The thing looked quite dirty as a waft of ketchup smell hit her. She was down wind from him afterall. Continuing her observations she saw baggy gym shorts and then a pair of white fuzzy slippers. They were dirty probably from being used outside that made her face turn to scrutiny.

A blush of embarrassment formed across the bridge of her nose as she realized she had been staring at him for far too long. He was even holding out his hand towards her that she darted her attention to. Well guess monsters were real. Either that or she was having a vivid hallucination.

When the ends of his skeleton fingers curled slightly she was jarred back to reality. He raised an eyebrow to her silent observing that she was not entirely sure was possible. Despite him being a skeleton he showed expression well.

"scare ya outta yer skin?" A chuckle erupted from him, not as menacing as she heard before though. Her body had relaxed, releasing the front of her coat. He seemed friendly enough though as he flexed his hand at her again. "leavin' me really bone-dry here."

"A-ah, I'm sorry! It's just," she spoke with a squeak in her tone. She could not help it as the situation went from really scary to kind of awkward fast. Her hand did not move towards his, instead she rubbed the back of her neck again as she muttered, "you're a monster and I kind of didn't believe they existed."

His hand curled back at the words, but his expression still seemed friendly as he stuffed his hands into his jacket pockets. She could not help but noticed how relaxed his posture was, fitting to his outfit style while he looked off to the side for just a moment. It was as if he was having an internal conflict.

"ya, well, we ain't havin' the easiest time fittin' in," he explained as the white lights in his sockets grew dark. The action was bringing her fear back as she moved her hands down to hug her chest.

The lights came back on as they darted down at her chest just as she had put her arms there. Was he looking at her...? The lights darted back up to her face just as fast as his grin seemed to hitch a bit higher. A blush crept up on her face as she tried to ignore her dirty thought to the motion. She had always considered herself kind of a freak, staying up late nights watching monster movies. Not for the scary aspect, but because she liked the monsters in more than one way or another. Now there was a real one standing just in front of her.

"What did you want," she questioned to get her wandering thoughts out of her head. Unbeknownst to her he was drinking in every reaction she made. He was far too observant, giving a shuffled step closer to her. As if predicting her reaction he watched as she jumped ever so slightly. Her eyes opening a bit in fear, however her face was beat red. It made his grin twist mischievously.

"nothin', girlie. ya just seemed cold and," he began, trailing off in the middle of his sentence as she could see him lowering his bottom jaw some. It revealed the tips of his teeth showing off the pointed tips and darkness between them. She found herself staring at the sight, her body heating to seeing such a thing in real life. He snapped his jaw shut which promptly made her jump before continuing his words, "ya shouldn't be walkin' out here alone and all. a bad monster might."

He stopped his words on purpose to let his eyes go dark. Why was she feeling such things towards a literal walking skeleton she just met? His voice began to leak out again though, "eat ya."

Okay now he had to be purposely hitting her buttons, her heart racing at the words. She did not even notice her jaw clenched and fingertips pressed into her palms until both started to ache. However just when she thought things would be taking a scarier turn he began to chuckle, the lights coming back in his sockets.

"nah, i'm messin' with ya, kiddo," he huffed in the middle of his laughter. She looked dumbfounded by the sudden change in tension. She could feel a prickle of a tear at the corner of one of her eyes due to her unease. Her body relaxed completely now though as she could not help but return the laugh shamefully while he spoke again, "name's sans, sans the skeleton."

"Yeah, nice to meet you," her words were almost muttered in disappointment. His expression did not change though as he casually walked closer to her. Was she really almost wishing he had stayed creepy like the movies she fantasized over.

"ya really shouldn't be walkin' out here alone, tho. lemme walk with ya," Sans hummed before giving a wink at her. Well he was charming at least. Or what few people would think as he seemed rather slob-like with his messy attire.

"I guess it couldn't hurt. Besides I'm shocked that there really are monsters in the woods," she was speaking more friendly now, warming up to the skeleton. He glanced up at her while they began walking side by side down the path. Every time she looked ahead to make sure she was not tripping over something his eyes darted down to take in her form. The red of her jacket making his eyes pulse with anticipation.

"ya, well ya humans ain't too easy to take in either," he retorted which made her feel as though she had insulted him. She frowned, staring down at him with guilt which he returned by giving a fake expression of being hurt. It was over dramatic which made her instantly regret her feeling of guilt. He began to chuckle as she caught on.

"Yeah, I know. It's just you know. Monsters are scary creatures that go bump in the night," she laughed with him after her words. He perked up though to her mention as he moved his hands out of his pockets to give an expressive shrug.

"i dunno, lady. us monsters can still go bump in the night," he huffed, his grin hitching again towards her. Oh no her dirty thoughts crept in again as all she could think about was making a lot of bumping in the night. She cursed at herself to stop thinking that, giving her head a shake.

"So, where do you all stay," her question was sincere as she was gave him a friendly smile now. He seemed to be enjoying her accepting him so well as he was used to people just running away. Must have been his lucky night.

"some went back into the mountain til we can find better livin' situations out here. our child ambassador ain't goin' so well," his words were so casual that she could not read his emotion towards the situation. She felt badly though that they were having troubles. No wonder all she ever heard was that there were terrible monsters in the woods. People must have been terrified of them.

"Well, I do hope things clear up then. You don't seem so bad afterall," her words flowed out with concern before she nodded at him. He stopped his walk though which scrunched her eyebrows with a bit of concern. She stopped as well to look back at him with question. The lights in his sockets dimmed ever so slightly. What was he thinking?

"think so?" The lights came back as he looked up at her with a look as though he liked what she had said. It was adorable as she felt herself falling for the monster. He then extended a hand towards her, flicking his fingertips at her for her to take it whiles he said, "you should come meet my bro. he absolutely loves humans and hasn't gotten to meet any friendly ones besides the kid."

Her smile sank into a frown though at his words. Seeing her expression his grin also twitched down. She was quick to wave her hands though as if to try to ease his saddened state to her possible rejection.

"I would really love to, but I have someplace I have to be," her words were full of regret as she genuinely wanted to go. She looked off to the side, thinking over it again for a moment. Did she really need to be on time? Maybe she could be late. Her vision was down at the ground for that thought process before looking back up to his hand still outstretched at her.

"c'mon, it won't be long, promise," he almost purred out the request pleadingly. It made her heart flutter as she could not resist it. With a deep regretting sigh she set her hand into his. The bones were about what she would have expected, she still flinched though when he wrapped his fingers around her hand. They were cold in the wintertime air. The texture was hard and coarse as he excitedly already started to tug her off the path.

With how friendly he was being, and dare she say a bit adorable, she did not really think over how suspicious it was to be taken off the path. Thankfully she was wearing sturdy high top boots, but the heels still sunk into the less sturdy ground making her fumble around. He seemed less caring to her footing as he tugged her arm a little harder while they walked.

"Slow down there, it doesn't have to be too quick," she laughed under her breath at the mention. There was silence though. He was not laughing back and his face was away from her since he was leading. Not long after her comment he had stopped abruptly. She nearly crashed into his back as she looked down at him with concern. Why did they stop already? They were still just in thick brush in the woods.

"it does have to be quick though," his words leaked out like the tone from before they had met. When he was just cackling at her through the empty woods to toy with her. She did not question it right away though as she looked around curiously as if expecting there to be more to the place they stopped.

"Is this like a secret entrance thing to the monster's lair," her joking question was followed by her laughing some. This time he did return it, it was low toned though which lit up a bit of fear. Her hand was still in his as she tried to pull it away. He held tighter when she did.

She felt herself tugged harshly towards him, yelping as his bony fingers threatened to cut into her hand. He now gripped at her other arm while standing in front of her. His mouth was opened just slightly as she could feel his hot breath hit her chin and neck. Her aroused blush from when they first met flared up as she looked down at him with confusion. He then leaned forward, taking a deep breath as if taking her scent in. His eyes pulsed lightly with the sensation.

"i could smell ya the second you entered the woods. gettin' turned on by enterin' the scary forest full of monsters, girlie," his breath hitched into a question. She was so shocked by what he was saying, but the wheels started spinning. He was pulling her away from the safety of the path.

She was so conflicted between being scared of a monster tearing her apart, or so incredibly heated by the same notion. Her words choked in her throat, unable to give him a response. Her body began to tremble as his hands released her, however hovered up near her face.

"shhh, don't worry, girlie. the big bad monster's got ya," he cooed her while the cold digits pressed against her heated face. It made her flinch, but there was only one hand on her cheek. The other outlined her jaw in a near intimate fashion. Then in a swift motion it clamped around her exposed neck causing her to take in a sharp breath.

"W-what," she squeaked, but he only made another 'shush' noise at her while she could feel herself being lead backwards until something hard poked her shoulders. Her back was now against a tree that tore her attention from him to glance at it.

The hand on her face pulled from her distracted expression to snap down, prying at the buttons of her jacket. He was working to yank the pretty red thing off her which now she began to struggle lightly against. It was weak though as her thighs were rubbing together from her obvious arousal. Was she really letting a monster do what she could only hope he was going to? Wait, what if he was literally just wanting to eat her. Fear lit up in her eyes, however he saw it immediately, drinking it the delicious sight.

"what? thinkin' bout how i might eat ya," he questioned full of amusement. She wanted to snarl at him, but held her tongue, only frowning to his words. To respond to her reaction he gave her neck a good squeeze, forcing a squeak out of her. My god it felt amazing as the pressure around her throat caused her a split moment of bliss. He did it only for a second before using both hands to yank open the coat.

He was wasting no time grabbing at her waist, kneading the flesh through her thin shirt. It elicited a moan out of her as she brought a hand up to nip at her knuckle and hide her shamefully aroused expression. She let him grope and grab at her before his hands slipped up under the shirt, trailing bony fingers upward.

"humans are so soft. makes ya wanna just," he groaned towards her, panting now in his own growing heat. "dig in," he purred while his hands slipped to her back, fingertips pressing into the skin as he pushed himself closer.

His mouth opened wider, the teeth looked even more menacing now that took her attention fully. She saw something from between them though in the darkness as it was a glowing blue light. This made her curious as she subconsciously reached out towards his mouth. Her fingers stopped just before touching his bottom row of teeth.

"mm, yer so interested in my mouth, girlie." Now what she was so curious about flopped out from the opening, lapping at her extended fingers. It was a warm and slimy tongue as it lathered over her skin, urging her hand closer. It felt like thick honey, but with a more solid middle. It stuck to her finger, leaving gooey residue while her fingers wiggled to the sensation.

One of his hands moved away from the warmth under her shirt to grab her wrist of the hand he was licking. He pulled it closer as he slipped his tongue up her palm. The feeling was incredible as she had never had such a thing touch her skin. At least not one that was living, moving against her fingers as it curled around them.

"ya taste so good," he grunted in a husky breath. Her hand was now drenched in the neon blue residue as some of the same color in drool dripped down his jaw bone. The hand still under her shirt pulled forward to grip at one of her breasts through her bra. The sudden action made her moan almost immediately as she was so distracted by his tongue.

He released her hand and moved his tongue away leaving a string of goo still connecting her fingers to him. Now he worked both hands to shove her bra up under her shirt so he could grab at her newly exposed breasts. Sure, she still had her shirt on, but it was loose enough for him to rub his hands over her chest with fascination. With the cold air she was somewhat thankful he was not pulling it off.

"humans have so many squishier places." His hard fingers fumbled across her nipples unknowingly which made her breaths quicken to the feeling. He did not seem entirely knowing of what he was doing, just excited in the feelings of the soft flesh.

"W-wait, how do--," she tried to question how monsters even did sexual acts, but that sloppy tongue pulled up to press against her open mouth. It dripped against her lips, falling into her mouth before he outright thrust the appendage in. The taste was rather unexpected as by the color she expected something more fruity. What she got was a salty ketchup flavor, but the texture was amazing she could not find room to complain.

His tongue explored her mouth hungrily before she realized it was going down further into her mouth. It was far longer than she would have expected causing her to reel back at the sensation of it brushing the outline of her throat. Just out of that reflex she had pulled her head away, but he only pushed forward more. Her tongue fumbled against the texture of his, unable to get any sort of traction against it while it slopped around in her mouth.

The residue it leaked was now becoming too much as she gave a light swallow to let it drain down her throat. She could not really worry about it being toxic to her system as he growled at her in approval. Just as fast as it had shoved into her mouth the tongue slipped out with a slick slop.

"i really gotta eat humans more often," his words came out perfectly despite his tongue still flopped out of his mouth. The blue saliva leaked out of her's, coating her lower lip while her face was in a haze of pleasure. She was so completely enthralled by the moment she did not feel him fiddling with her pants at first. Coming back to reality she saw him already growling at her tight fitting pants, trying to push them down her shapely thighs.

Ignoring the logical side of her brain questioning her actions or even how monsters did things she aided him in yanking them down. Once they got to her knees though he gave violent tugs which pulled her legs out from under her. Her back slid against the bark as she fell down on her ass.

"heh, have a nice trip?" Thankfully her bare ass had landed on her jacket under her, yet still stung sending a throb through her lower back. She saw him drop to his knees, his hands still in the mess of her pants and underwear around her calves.

She almost wanted to laugh at the fall, but she was so clouded by lust while staring up at him. His right eye socket had gone dark as she saw his left one was flared up in a blue color. It matched his tongue which still sloppily hung from his mouth while he panted at her. The middle of the eye pulsed a yellow color when he made tugs at the fabric.

One of his arms wrapped around her legs as they were still constrained together by her pants. He began to fiddle with his shorts as she now watched with curiosity, readjusting herself against the tree. He pulled down the front of his shorts to reveal a materializing blue hard-on. Its length was not too much more than average, however the girth was intimidating. It looked more like an exotic sex toy than an actual penis. Except that it was of the same texture as his tongue and just as gooey.

"like what ya see," he questioned smootly to seeing her look at his length. Her head nodded in response, biting down on her still wet lip. She was so glad she was sopping wet, her folds glistening in the glow of it. That and the slick residue leaking off the thing should surely provide a lube itself.

He did not seem to know enough about what he was doing to prepare her or anything. His hands grabbed at the annoying pants now being held on her calves still by her boots being in the way. A frustrated growl came from him as he looked down at the situation to think for just a moment.

"H-here, I can," she tried to help with her breaths as heavy as his. He was not listening though as he kept her legs pressed together and moved her feet to set on one of his shoulders. One of his hands guided the tip of cock against her entrance. It was so slick it slipped between the lips sloppily. She was already shivering from just the contact against her swollen heat.

The rubbing around her entrance felt amazing as she wiggled around ever so slightly. It was not intentional though as the head slipped into her hastily. A satisfied grunt came from him as she really expected him to savor the feeling. He did not as he rammed into her roughly.

"A..ah, slow d-down," she whimpered, although her body jolted in pleasure when he started bucking into her like an animal in heat. His hands grabbed down at her hips to steady them while her legs bounced against his chest. It felt amazing like an overly lubricated toy, but the girth stretched her enough to cause that light burn to her entrance.

Her walls though tugged at him and loved the feeling as he was thrusting into her at sloppy angles. Once in a while he hit those sweet spots that made her twist and moan in pleasure. After it had started her brain was only just catching up to what was going on. A monster was fucking her in the middle of the woods against a tree. Said tree was her only support as one of her hands reached up to try to brace herself to the rough pounding.

Sans had gone quiet since getting his length in as he was taking full advantage of the moment. He let out various growls of enjoyment following heavy breaths while his glowing blue eye was transfixed on what was going on. She let out a raunchy moan that was a bit louder than normal which caught his attention.

"g-guess ya know what it's like to have a-another skeleton inside ya," he strained to huff out the joke. She wanted to giggle at it, but he shifted himself closer, pressing her tighter towards the tree while he leaned down over her. Her legs were still pressed against his chest as they moved with his leaning. He was trying to push himself deeper as he was already hilting himself with his thrusts. Her thighs parted in whatever way she could just to feel more of him, moaning lightly to the sensation.

She really wanted to untangle her legs, but the merciless humping was too intoxicating which made her hips roll against his. Her body jolted uncontrollably to him hitting those spots even more often now. He was learning as he watched her face with enjoyment. Every time she flinched with a moan his cock swelled slightly.

Her limits were reaching as she felt her body trying to lock up. She could not believe she was having the hottest orgasm ever to a skeleton fucking her brains out. Her walls clenched tightly on him as he continued thrusting away which sent her over the edge. She trembled hard as her tongue lolled out in the moment, completely overcome by her orgasm.

"scream for me, human," he demanded making her yell out a pleasuring noise. He was drinking in her expression which only made him thrust even more erratic. He was so close even though she was coming down from her bliss. When she was able to focus again she breathed in hard. Whimpered squeaks escaped her as she began to struggle some because he was going at it harder than he had before. She was being over stimulated, choking on her own breath as her hand went up to grab at his jacket.

She wanted to tell him to cum outside, but she could not form the words. Only incoherent whines escaped her panted breath. He was already at his end as he pressed in as deep as he could, his pelvic bone digging into her ass as he released. The rushing warm liquid filled her up as she did not know it could get even more flooded inside her than it already was. The excess dribbled down the sides of her folds, falling on her jacket below them.

He was giving heavy groans of pleasure in his release as he finished pumping her full of the neon blue seed. Her back was arched in the amazing feeling, tears prickling the corners of her eyes. His cock slopped out and back in a couple of times before pulling out with a noticeable plop.

The mixed juices drizzled out from her well used entrance as she was panting, catching her breath. He sat back on his knees while her legs still hung from his shoulder. He casually pulled up his shorts as the blue glow fizzled out from view.

Her legs prickled with numbness as she was still trying to recover. Slumping down some she did not even care about how dirty her jacket was getting from both being on the ground and the fluids dripping down on it. Her hair was tangled lightly on the bark of the tree behind her as she was a complete mess.

His hand patting at her bare thigh jolted her some, making her whimper out a pleasing squeak in response. She was still so sensitive to the slightest touch.

"such a dirty human lovin' a monster takin' her in the woods," he mused at her, lowering her legs. He moved to slip her panties and pants up, not giving a care to the fact she was still dripping with his seed. Or maybe that was his intention to not have it washed away as he finished buttoning up her pants.

Her hands wanted to help dress herself, feeling guilt of being so helpless after such an experience. However she was completely out of it while not even sure how to respond to him now. It had been the best fuck she had ever gotten. His amused chuckles woke her up as he began to stand up. She mumbled shamefully, trying to bury herself deeper into her jacket while also pulling her bra back into the right position.

He stood over her though, leaning down to hoist her back up to her feet. He lifted her as if she was nothing which was surprising as she huffed to being set back down on her wobbling legs. She could not stand right away which he realized as he held her against him.

"That was amazing," she finally spoke, her voice cracked just slightly from all the moaning she had been doing. Sans perked up to her words before huffing out a laugh, rubbing his hands down her back some to touch at the softness a bit more.

"that so? maybe i should keep ya. paps always wanted a pet human afterall," he hummed casually, the words made her almost moan out from the small jolt of arousal she got. His hands squeezed at her ass as his grin widened to seeing her reaction.

"As much as I would love to say yes, I really do have to be somewhere," she panted out the words, although his hands were groping needily at her ass in the mean time. He did not release her as she made the move to pull away from him. He was giving off an almost possessive stance as he growled to the movement she made. After a split moment he stopped though and released her hesitantly.

"yeah yeah, lady. still let me walk ya. don't need you out in the woods alone afterall," he said in that deep vibrating tone that sent wonderful chills up her spine. Oh yeah he knew her buttons already in such a short time. She would definitely have to come back.

Unless he does not let her leave.


End file.
